In various operations conducted via underground wells, it is often advantageous to be able to assess the geometry of the well or surrounding area. One example is in the mapping of hydraulic fractures in hydrocarbon production wells. Hydraulic fracturing is a widely used process for stimulating oil and gas wells and typically involves injecting fluid into the well bore at a higher pressure than the surrounding reservoir pressure. The higher pressure of the injected fluids causes the formation to fracture and thereby increase the surface area through which oil or gas may flow, thus increasing overall productivity of the well.
Once hydraulic fractures are formed, it is believed to be advantageous to learn about or map out the geometry or dimensions of the fractures, such as to increase the effectiveness of the fracturing process and hydrocarbon production. Existing techniques for visualizing underground geometries, such as hydraulic fracture propagations, include micro-seismic fracture mapping, tilt-meter fracture mapping and the use of tracers. These techniques are believed to have one or more drawbacks or limitations. For example, some of these techniques are believed to be limited to representing only one dimension of fracture geometry (e.g., length, height, depth, or azimuth). In some mapping techniques, fracture height may only be measured at the well bore. For other examples, some of the current mapping technologies require the use of an offset well, which may dramatically increase costs, and/or radioactive material, which may be environmentally damaging.
It should be understood that the above-described discussion is provided for illustrative purposes only and is not intended to limit the scope or subject matter of this disclosure, the appended claims or the claims of any related patent application or patent. Thus, none of the appended claims or claims of any related patent application or patent should be limited by the above discussion or required to address, include or exclude the above-cited examples, features and/or disadvantages merely because of their mention above.
Accordingly, there exists a need for improved systems, apparatus and methods capable of mapping underground areas or features from a subterranean well and having one or more of the attributes, capabilities or features described below or evident from the appended drawings.